Investigation described as a 'volatile'

MACK, Colo. - Federal agents and Utah state troopers are investigating the suspected illegal smuggling of immigrants into the country after four men were killed when a crowded van crashed on Interstate 70 about 30 miles from the Colorado line.

U.S. Immigration and Customs Enforcement agents say they have detained three of the four men who survived the crash. They continue to search for a woman who fled the scene about 4:30 a.m. Friday.

Utah Highway Patrol Sgt. Todd Royce says all four of the men who died were undocumented immigrants from Mexico and El Salvador.

He told The Salt Lake Tribune they still are trying to identify some of the victims. He says all names are being kept secret to protect what he describes as a "volatile" investigation.

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